I've been playing green the entire BT-03 meta, and as the meta comes to a close this coming weekend I figured I'd write a bit about this deck that has served me quite well. As we all know [BT3-056] Ceresmon was the green meta card everybody was waiting for, being the most hyped-about green card during the BT-03 leaks. However, despite her speed in digivolving I find her lacking in firepower and robustness. It is disastrous if you fail to draw into a Ceresmon early in your hand, or if was she removed (one way or another by Option cards or effects) prematurely. With half of your deck geared towards having Ceresmon in play, you will have a hard time recovering if you no longer have her on the field.
The problem with Ceresmon
I find Ceresmon decks quite rigid. To take advantage of her effects, use close-to-maximum copies of digimons with <Digisorption>. These include [BT2-045] Argomon, [BT2-047] Argomon, and [BT3-054] Blossomon. With Ceresmon also being the main cannon, blockers are needed for protection: [BT1-072] Woodmon and [ST4-08] Kabuterimon. These constitute half the deck, and dictates a general and predictable playstyle with little room for surprise element.
This is Not a Ceresmon Green Deck
[BT1-089] Mimi Tachikawa provides consistent 3-memory during the start of turn, which is essential for executing combos. She also speeds up your game and provides very memory efficient digimon-fielding. Play her early.
If you do not have Mimi, [BT3-094] Ken Ichijouji makes a decent alternative.
The LV4 and LV5 digimons in this deck are all cost-effective. Digivolve into [BT3-057] MegaGargomon to rest the opponent's digimon you plan to attack/destroy the next turn. He does not give away too much memory (unlike Puppetmon) so it is unlikely that he can be removed by a LV7 digimon effect, and his DP will be buffed by the inheritable effects of his LV3, 4 and 5 digimons.
[BT3-111] Imperialdramon and [ST4-13] HerculesKabuterimon are also played for highlander-style versatility (to avoid drawing both of the same cards in my hand). Both are equally great with <Piercing> and can be digivolved in the nursery (if needed).
Note: I have replaced Hercules with Bancho in my decklist, feel free to swap a BanchoStingmon for a Hercules.
[BT3-058] BanchoStingmon is the other star of the deck (aside from MegaGargo). He can tilt the game with a single, properly planned attack.
I usually play him with [BT2-047] Argomon for a surprise digivolution from LV4 to LV6 costing just 3 memory (guaranteed if you have Mimi). If there is another threat on the field that might attack a suspended BanchoSting, I will digivolve another digimon into a MegaGargo, given I have another LV5 or LV4 and a Argomon in hand.
I play 2 copies of [BT3-103] Hidden Potential, not too many as they might lock my hand. This card is useful to almost all my LV6 digimons, including BanchoStingmon if I do not have enough memory. Memory can be scarce if Mimi is not in play, or if I need them for [ST4-15] Chiku Chiku Bang Bang!
I prefer Chiku Chiku Bang Bang over Flower Cannon for the simple fact that it can rest even blockers.
LV5 and Below
For LV3, 4 and 5 digimons, I emphasize digimons that grant DP buffs and low digivolution costs. With properly stacked DP buffs, even BanchoStingmon can easily surpass a 11000 DP digimon (since his secondary effect will not trigger) and MegaGargomon can surpass even a 15000 DP LV7 digimon.
I've built this deck for robustness: no one card cannot survive without another, and every card has a certain synergy with another. This deck has gotten me out of sticky situations numerous times, and most importantly is technical and loads of fun! I am looking forward to further optimizations with [BT4-090] Chaosmon once BT-04 lands!